More iPhone 3 Development: Tackling iPhone SDK 3

Chapter 2. The Anatomy of Core Data

Core Data is a framework and set of tools that allow you to persist your application's data to the iPhone's file system automatically. Core Data is a form of something called object-relational mapping, or ORM, which is just a fancy way of saying that Core Data takes the data stored in your Objective-C objects and translates (or maps) that data into another form so that it can be easily stored in a database, such as SQLite, or into a flat file.

Core Data can seem like magic when you first start using it. Objects are simply dealt with as objects, and they seem to know how to save themselves into the database or file system. You won't create SQL strings or make file management calls—ever. Core Data insulates you ...